Collet attachment.



No. 866,788. PATENTED SEPT. 24, 1907.

- J. L. HOLSTEIN. COLLET ATTACHMENT.

LPPLIOATION FILED 00T. B. 1908.

Z SHEETS-SHEET 1.

No. 866,788. I PATENTED SEPT. 24, 1907.

J. L. HOLSTEIN. CO'LLET ATTACHMENT.

APPLIOATIOI FILED 00T. 8. 1906..

2 SHEETS-SHEET 2.

N fw- V5.1 zo 2/` UNITED STATES PATENT oEEIeE.

JOSEPH L. HOLSTEIN, OF CLEVELAND, OHIO, ASSIGNOR TO THE ADJUSTABLECOLLET COMPANY, OF CLEVELAND, OHIO, A CORPORATION.

COLLET ATTACHMENT.

Specification of Letters Patent.

Patented Sept. 24, 1907.

. 4 Application iiled October 8, 1906. Serial No. 837,906.

To all whom it may concern:

Be it known that l,JosErH L. oLsrErN, a citizen of the United States,residing at Cleveland, in the State o Ohio, have invented certain newand useful Improvements in -Collet Attachments, of which the followingis a speciication.

My invention. relates to machines of the general type of a turning latheor commonly called collet machine and its primary object is to providemeans for converting any machine with a bed plate and rotating spindleinto a collet machine.

Other objects are to provide an adjustable collet attachment which canbe pnt on and removed instantly, and to provide certain improvements inthe construction of self adjusting collets.

These objects and other ladvantages to appear hereinafter are attainedby the construction illustrated in one form in the accompanying drawingswherein,-

Figure l is a vertical central section oi the principal parts of mycollet attachment, with the support in side elevation. Fig. 2 is a topplan view of the same. Fig. 3 is a lfront elevation of the attachment.Figs. 4 and 5 are sections of the collet shown separately, in two forms,respectively a pull collet and push collet. Figs. 6, 7 and 8 are frontviews oi several arrangements ofthe collet jaws for accommodatingdifferent shaped stock rods. Ordinarily collet machines are especiallydesigned, and the collet operating 'means are a permanent part oi themachine so that the machine can be used for nothing else but workingstock adapted to a collet; and the collets4 are made with solid jaws anda set of them are required in order to accommodate more than one size ofstock. Again it is customary to work the collet from the rear end of themachine, and the bearings are the ordinarybearings of the spindle atconsiderable distance from the collet, often requiring a separatecentering rest where the article is of any length. In order to convertany machine, such as a-lathe, into a collet machine, I provide aportable attachment adapted to readily fit any machine having a rotatingspindle.-

Inthe drawings it will be seen that I have provided a frame l0 whichcarries a centering head ring 11 provided With adjusting screws 12within which is placed a bearing ring 13. ln this` bearing ring is ahollow spindle 14 which is adapted to screw upon the end oi a livespindle as shown at the leftof Fig. l. The spindle 14 is provided with apair of oppositely disposed slots into which extend bell crank levers 15pivoted upon an adjustable ring 16 sliding upon the spindle l4. Asupplemental screw ring 17 is provided in order to lock the ring 16 inplace so that the position of the bell crank levers 15 may be adjustedand fixed at any distance from the front end of spindle 14. Inside thespindle 14 is provided an actuating ring 18 to which is attached thecollet 19 having gripping jaws. The collet has a bearing rib 20. Thegripping jaws shown at 21 are made in the form of pins set in slots andheld in place by a screw ring 22, so that they work in a radialdirection. These gripping jaws are normally h eld outwardly by springs23 and it will be observed that they have tapered outer faces whichengage a tapered bearing ring 24 set inthe front of the spindle 14. Inorder to work the collet jaws by means of the bell crank levers 15 thereis the usual sliding Wedge ring 25 in the peripheral slot 26 of whichoperate the pins 27 provided on the end of arms 28, the arms 28 beingreciprocated when desired by means of the xed shaft 29 and handle 30arranged either as shown or horizontally in the usual manner.

The" entire collet attachment is easily attached to or removed from anyspindle by means oi a proper collar 32 and tothe lathe bed by means ofbolts 31 as will be apparent, and the adjustment of the collet in linewith the machine spindle is readily made by means of the screws 12 12,of which the former are arranged to slide on the iiat surface'lS (Fig.3). The collet 19 may, of course, be arranged for a pull collet as shownin Fig. 4 or as a push.collet as shown in Fig. 5, by

merely reversing the direction of slope o the bearing surfaces on theclamping jaws 21. These 'clamping jaws may of course be provided in anynumber desired and given the various forms shown in Figs. 6, 7 and 8 inorder to operate upon any shape of stock as desired.

It will be seen that by the above described structure the colletattachment may instantly be applied to the live spindle of a standardlathe or other similar spindle and the centering of the collet isreadily made, and that the operation is that when the lever. 30 is movedto cause the wedge ring 25 to come under the bell crank levers 15, theselatter act to draw the collet 19 within the conical ring 24 which latterthereupon engages the outer ends of the gripping jaws 22 and thruststhem down in a radial direction upon the stock. The centering of thecollet being accomplished by the rib 20, the contact of the grippingjaws with the ringV 24 is not depended upon to center the gripping jawsand therefore they are self adjusting so that they will allow for anyirregularity in the stock. It will also be seen that the thrust upon thegripping jaw is direct in a radial direction and that the play oi thejaw depends merely upon the distance it moves within the sloping ring24. It is also evident that by providing 'several sets of the simplepins 2l withone of these attachments the collet can be instantly changedto t different sizes of stock by removing the holding ring 22 andsliding the pins 21 out ofthe slot in a forward direction. The

springs 25T-'are set to one side of the pin-'21-as will bgpf parent, inorder to avoid weakening the pin and also to convenientlyhold the springin its place inthe collet head. l

It will be recognized that it is a greatl advantage to be able to steadyand center the collet at its extreme end by means oi the ring 13 and therib and that by means oi the screw ring 16 and thelock ring 17 -thethrow ci the collet jaws can be securely and instantly adjusted.inasmuch as the only wearing'bearings in the collet are on the pins 21they` alone will need to be hardened and this very much increases thelife o the collet. The collet can be made -to draw or push by simplychanging the ring 24 and reversing the position of the bell crank leversl5, while the whole attachment being placed on the iront oi the machinerenders it far more convenient than heretofore.

A particular part of my invention is the self adjusted automatic colletitself with its interchangeable jaws, and the ease with which they maybe ground to exactly fit the bearing ring 24, whatever may be the lengthof the jaw pins.

It is to belnoted that the collet may be adjusted in the amount of throwof the jaws or the jaws may be interchanged without removing it from themachine. O/tlier advantages will readily occur to those familiar withsuch machinery.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent, is the following:

1. In a universaly collet attachment the combination of a portableframe, a hollow spindle mounted in the frame, means for connecting therear end of the spindle to a live spindle and the frame toa lathe bed, achuck in the front end of said hollow spindle, and means in the frame toadjust and center the alinement of the front en'd of the spindle. n

2. The combination with a portable collet frame and means thereon toattach it to a lathe bed and to radjust the aiinement of a' collettherein, of a hollow spindle mounted in the frame, acollet with'gripping jaws mounted in the spindle, 1nd means on the spindle tooperate thegripping jaws of the collet, substantially as described.

3. A collet attachment comprising a frame, a bearing ring thereinadjustable transversely'of its axis in all directions, a hollow spindlein the ring, a collet in the spindle having radially slidable grippingjaws, and means sesgos for moving the collet longitudinally of thespindle and' connections between the spindle and the jaws by which suchmovement ot the collet moves the jaws radially.

4. The combination with a revoluble shaft having a conical bearingsurface therein, of a slotted collet head, means to center it in saidshaft, a series of gripping jaws mounted to slide radially in the slotsin said head, means to hold said jaws removably in the head.

.5. In a collet the comblnrtion with a hollow shaft with a conicalmouth, of a head 19 provided with longitudinal slots, a series of blocks2i slidably mounted in the slots to engage the said conical'shaft mouth,and a retaining means to hold the blocks in the slots, the collet headbeing provided with a separate centering and bearing rib 20,substantially as described.

6. The combination with a conical mouthed tubular spindle, of a collethead mounted therein having radially sliding blocks tor gripping, meansto move the collet head 'in the conical spindle to operate said jaws,and means to adjust the initial position of the collet head in thespindle to regulate the radial capacity of said jaws, substantially asset forth.

7. The combination with u conical bearing sleeve there for, of :i collethead comprising a hollow shaft with a slotted conical end, said slotsopening to the end of the collet head, radially sliding blocks in theslots of the head and means for removably holding the blocks in thehead, including a removable holding device closing the,ends of the slotsin the collet. whereby the blocks may be removed without removing thehead from the said sleeve, sulr stnntially :is described.

8. The combination of :i portable frame having means to attach it to nlathe bed, v:l rotatable hollow spindle mounted therein having means toattach it to a lathe spindle, chuck-jaws in said rotatable spindle,means to operate them and :in adjustable supporting ring in said framefor :ilining said hollow spindle.

9. As an article of manufacture n collet head comprising a hollowspindle having a bearing rib thereon, slots in the end of the spindle,radially operating jaws in said slots and u removable screw ring adaptedto retain the jaws in the slots, substantially as described.

10. In a collet attachment the combination of a bearing cone, a hollowspindle sliduble in said cone and having radially movable jaws engagingthe cone, and means independent of said jnws to center the hollowspindle within the bearing cone.

In testimony whereof I have hereunto signed my name in the presence ofthe two subscribed witnesses.

JOSEPH L. HOLSTEIN.

In presence of- JUnlUs Srrrz.

AARON IIAH N.

